<template>
    <view class="vue-cropper" ref="cropper" :style="{top:`${containerTop}px`}" v-show="show">
        <view class="cropper-box">
            <view class="cropper-box-canvas" @touchstart.stop.prevent="imgTouchStart" @touchmove.stop.prevent="imgMoveing" @touchend.stop.prevent="imgMoveEnd" :style="{
			'width': imageWidth + 'px',
			'height': imageHeight + 'px',
			'transform': 'scale(' + scale + ',' + scale + ') ' + 'translate3d('+ x / scale + 'px,' + y / scale + 'px,' + '0)'
			+ 'rotateZ('+ rotate * 90 +'deg)'}">
                <image :src="src" alt="cropper-img" ref="cropperImg" mode="scaleToFill" class="uni-image"></image>
            </view>
        </view>
        <view class="cropper-drag-box cropper-modal cropper-move pointer-events"></view>
        <view class="cropper-crop-box" :class="{'pointer-events': cropFixed}" :style="{'width': cropW + 'px','height': cropH + 'px','transform': 'translate3d('+ cropOffsertX + 'px,' + cropOffsertY + 'px,' + '0)'}">
            <view class="cropper-view-box">
                <image :style="{'width': imageWidth + 'px','height': imageHeight + 'px','transform': 'scale(' + scale + ',' + scale + ') ' + 'translate3d('+ (x - cropOffsertX) / scale  + 'px,' + (y - cropOffsertY) / scale + 'px,' + '0)' + 'rotateZ('+ rotate * 90 +'deg)'}" mode="scaleToFill" :src="src" alt="cropper-img"></image>
            </view>
            <view v-if="!cropFixed" class="cropper-face cropper-move" @touchstart.stop.prevent="touchStart" @touchmove.stop.prevent="cropMoveing"></view>
            <view class="crop-line line-w"></view>
            <view class="crop-line line-a"></view>
            <view class="crop-line line-s"></view>
            <view class="crop-line line-d"></view>
        </view>
		<canvas  id="myCanvas" canvas-id="myCanvas" class="cropper-canvas" :style="{ 'width': cropW + 'px','height': cropH + 'px' }"></canvas>
        <view class="btn-group">
            <view class="btn-item reset-btn" v-show="showResetBtn" @tap="init"></view>
            <view class="btn-item rotate-btn" v-show="showRotateBtn" @tap="rotateHandler"></view>
        </view>

        <view class="uni-info__ft" :style="{paddingBottom:iPhoneXBottomHeightRpx+'rpx', background:'#FFFFFF'}">
            <view class="uni-modal__btn uni-modal__btn_default" style="color: rgb(0, 0, 0);" @tap="cancel">取消</view>
            <view class="uni-modal__btn uni-modal__btn_primary" style="color: rgb(0, 122, 255);" @tap="confirm">确定</view>
        </view>
    </view>
</template>
<script>
export default {
	name: 'image-cropper',
	props: {
		cropWidth: {
			type: Number,
			default: 200,
		},
		cropHeight: {
			type: Number,
			default: 200
		},
		cropFixed: {
			type: Boolean,
			default: false,
		},
		src: {
			type: String,
		},
		showResetBtn: {
			type: Boolean,
			default: true,
		},
		showRotateBtn: {
			type: Boolean,
			default: true,
		}
	},
	data() {
		const sysInfo = uni.getSystemInfoSync();
		const pixelRatio = sysInfo.pixelRatio;
		return {
			show: false,
			scale: 1,
			rotate: 0,
			cropW: 0,
			cropH: 0,
			cropOldW: 0,
			cropOldH: 0,
			sysInfo: sysInfo,
			pixelRatio: pixelRatio,
			imageRealWidth: 0,
			imageRealHeight: 0,
			cropOffsertX: 0,
			cropOffsertY: 0,
			startX: 0,
			startY: 0,
			// 裁剪框与边界间距
			border: 5,
			x: 0,
			y: 0,
			startL: 0,
			oldScale: 1,
			iPhoneXBottomHeightRpx:0
		}
	},
	created:function(){
		const sysInfo = uni.getSystemInfoSync();
		const pixelRatio = sysInfo.pixelRatio;
		var iPhoneXBottom = 0;
		sysInfo.model = sysInfo.model.replace(' ', '');
		sysInfo.model = sysInfo.model.toLowerCase();
		if(sysInfo.model.indexOf('iphonex') != -1 || sysInfo.model.indexOf('iphone11') != -1){
			this.iPhoneXBottomHeightRpx = 50;
		}else{
			this.iPhoneXBottomHeightRpx = 0;
		}
	},
	watch: {
		src(val) {if(val.length > 0) { this.init();}},
		show(val) {if(!val){}}
	},
	computed: {
		containerTop() {
			let top = 0
			// #ifdef H5
			top = 44
			// #endif
			return top;
		},
		// 容器高度
		containerHeight() {
			return this.windowHeight - 48;
		},
		// 屏幕宽度
		windowWidth() {
			return this.sysInfo.windowWidth;
		},
		windowHeight() {
			return this.sysInfo.windowHeight;
		},
		// 图片宽高比
		imageRatio() {
			if (this.imageRealHeight > 0) {
				return this.imageRealWidth / this.imageRealHeight;;
			}
			return 0;
		},
		// 等比缩放后的宽度
		imageWidth() {
			if (this.imageRatio >= 1) {
				return this.windowWidth;
			}
			var imageWidth = this.windowWidth * this.imageRatio;
			if(imageWidth < this.cropWidth){return this.cropWidth;}
			return this.windowWidth
		},
		// 等比缩放后的高度
		imageHeight() {
			return this.windowWidth / this.imageRatio
		},
	},
	methods: {
		rotateHandler() {
			if(this.rotate == 3) {
				this.rotate = 0;
			}else {
				++this.rotate
			}
		},
		init() {
			this.rotate = 0;
			this.scale = 1;
			this.cropW = this.cropWidth
			this.cropH = this.cropHeight
			uni.showLoading({title: '图片加载中...',})
			this.loadImage(this.src).then((e) => {
				uni.hideLoading()
			}).catch((e) => {
				uni.hideLoading()
				uni.showModal({
					title: '标题',
					content: '图片加载失败'
				})
			})
		},
		loadImage(src) {
			const _this = this
			return new Promise((resolve, reject) => {
				uni.getImageInfo({
					src: src,
					success: (res) => {
					
						_this.imageRealWidth = res.width
						_this.imageRealHeight = res.height

						_this.cropOffsertX = _this.windowWidth / 2 - _this.cropW / 2
						_this.cropOffsertY = _this.windowHeight / 2 - _this.cropH / 2
						_this.show = true

						_this.$nextTick(() => {
							_this.x = _this.windowWidth / 2 - _this.imageWidth / 2
							_this.y = _this.containerHeight / 2 - _this.imageHeight / 2
						});
						resolve(res)
					},
					fail: (e) => {
						_this.show = false
						reject(e)
					}
				})
			}).catch((e) => {});
		},
		cancel() {
			this.show = false
			this.$emit('cancel')
		},
		confirm(event) {
			uni.showLoading({
				title: '裁剪中...',
			})
			const _this = this
			const ctx = uni.createCanvasContext('myCanvas', _this);
			const pixelRatio = _this.pixelRatio;
			const imgage = _this.src;
			const imgW = _this.imageWidth * _this.scale;
			const imgH = _this.imageHeight * _this.scale
			const rotate = _this.rotate;
			let dx = _this.cropOffsertX - _this.x - (_this.imageWidth - imgW) / 2;
			let dy = _this.cropOffsertY - _this.y - (_this.imageHeight - imgH) / 2;
			ctx.setFillStyle('white');
			ctx.fillRect(0, 0, imgW, imgH);
			ctx.save();
			ctx.rotate((rotate * 90 * Math.PI) / 180);
			switch (rotate) {
				case 1:
					dx += (imgH-imgW) / 2
					dy -= (imgH-imgW) / 2
					ctx.drawImage(imgage, -dy, dx, imgW, -imgH);
					break;
				case 2:
					ctx.drawImage(imgage, dx, dy, -imgW, -imgH);
					break;
				case 3:
					dx += (imgH-imgW) / 2
					dy -= (imgH-imgW) / 2
					ctx.drawImage(imgage, dy, -dx, -imgW, imgH);
					break;
				default:
				 ctx.drawImage(imgage, -dx, -dy, imgW, imgH);
					   //ctx.drawImage(imgage, 2, 2, 375,375);
					break;
			}
			ctx.restore()
				// #ifdef MP-ALIPAY
				ctx.draw(true, () => {
					ctx.toTempFilePath({
						destWidth: _this.cropW * pixelRatio,
						destHeight: _this.cropH * pixelRatio,
						success: (res) => {
							uni.hideLoading()
								event.detail.tempFilePath =res.apFilePath
								_this.show = false
								_this.$emit('confirm', event)
							},
							fail: (e) => {
								uni.hideLoading()
								uni.showModal({
									title: '提示',
									content: '裁剪失败'
								})
							}
					}, _this);
				});
			// #endif
			// #ifndef MP-ALIPAY
			ctx.draw(false, () => {
				uni.canvasToTempFilePath({
					canvasId: 'myCanvas',
					destWidth: _this.cropW * pixelRatio,
					destHeight: _this.cropH * pixelRatio,
					success: (res) => {
						uni.hideLoading()
						event.detail.tempFilePath = res.tempFilePath;
						_this.show = false
						_this.$emit('confirm', event)
					},
					fail: (e) => {
						uni.hideLoading()
						uni.showModal({
							title: '提示',
							content: '裁剪失败'
						})
					}
				}, _this);
			})
			// #endif
		},
		imgTouchStart(e) {
			if(e.touches.length == 2) {
				this.oldScale = this.scale
				this.scaling = true
				const x = e.touches[0].pageX - e.touches[1].pageX
				const y = e.touches[0].pageY - e.touches[1].pageY
				const hypotenuse = Math.sqrt(
					Math.pow(x, 2) +
					Math.pow(y, 2)
				)
				this.startL = Math.max(x, y, hypotenuse)
				uni.showModal({content: this.startL});
			} else {
				this.startX = e.touches[0].pageX - this.x
				this.startY = e.touches[0].pageY - this.y
			}
		},
		imgMoveing(e) {
			if(this.scaling) {
				let scale = this.oldScale;
				const x = e.touches[0].pageX - e.touches[1].pageX
				const y = e.touches[0].pageY - e.touches[1].pageY
				const hypotenuse = Math.sqrt(
					Math.pow(x, 2) +
					Math.pow(y, 2)
				)
				const newL = Math.max(x, y, hypotenuse)
				const cha = newL - this.startL;
				// 根据图片本身大小 决定每次改变大小的系数, 图片越大系数越小
				// 1px - 0.2
				let coe = 1;
				coe =
					coe / this.imageWidth > coe / this.imageHeight
						? coe / this.imageHeight
						: coe / this.imageWidth;
				coe = coe > 0.1 ? 0.1 : coe;
				const num = coe * cha;
				if (cha > 0) {
					scale += Math.abs(num);
				} else if (cha < 0) {
					scale > Math.abs(num) ? (scale -= Math.abs(num)) : scale;
				}
				this.scale = scale;
			} else {
				const moveX = e.touches[0].pageX - this.startX
				const moveY = e.touches[0].pageY - this.startY
				this.x = moveX
				this.y = moveY
			}
		},
		imgMoveEnd() {
			setTimeout(() => {
				this.scaling = false
			}, 100)
		},
		touchStart(e) {
			this.startX = e.touches[0].pageX - this.cropOffsertX;
			this.startY = e.touches[0].pageY - this.cropOffsertY;

			this.cropOldW = this.cropW
			this.cropOldH = this.cropH
		},
		cropMoveing(e) {
			const moveX = this._cropX(e.touches[0].pageX - this.startX)
			const moveY = this._cropY(e.touches[0].pageY - this.startY)

			this.cropOffsertX = moveX
			this.cropOffsertY = moveY
		},
		dragMove(e, type) {
			if(this.cropFixed) {
				return false
			}
			const moveX = e.touches[0].pageX - this.startX
			const moveY = e.touches[0].pageY - this.startY
			switch (type) {
				case 'left-top':
					this._cropMoveLeft(moveX)
					this._cropMoveTop(moveY)
					break;
				case 'middle-top':
					this._cropMoveTop(moveY)
					break;
				case 'right-top':
					this._cropMoveTop(moveY)
					this._cropMoveRight(moveX)
					break;
				case 'middle-right':
					this._cropMoveRight(moveX)
					break;
				case 'right-bottom':
					this._cropMoveRight(moveX)
					this._cropMoveBottom(moveY)
					break;
				case 'middle-bottom':
					this._cropMoveBottom(moveY)
					break;
				case 'left-bottom':
					this._cropMoveBottom(moveY)
					this._cropMoveLeft(moveX)
					break;
				case 'middle-left':
					this._cropMoveLeft(moveX)
					break;
				default:
					break;
			}
		},
		_cropMoveTop(y) {
			const topY = this._cropY(y)
			this.cropH += this.cropOffsertY - topY
			this.cropOffsertY = topY
		},
		_cropMoveRight(x) {
			if(this.cropOldW + x >= this.windowWidth - this.border) {
				return false;
			}
			this.cropW = this.cropOldW + (x  - this.cropOffsertX)
		},
		_cropMoveBottom(y) {
			if(this.cropOldH + y >= this.windowHeight - this.containerTop - this.border) {
				return false;
			}
			this.cropH = this.cropOldH + (y  - this.cropOffsertY)
		},
		_cropMoveLeft(x) {
			const leftX = this._cropY(x)
			this.cropW += this.cropOffsertX - leftX
			this.cropOffsertX = leftX
		},
		_cropX(x) {
			if(x <= this.border) {
				return this.border
			}
			if(x + this.cropW >= this.windowWidth - this.border) {
				return this.windowWidth - this.cropW - this.border
			}
			return x
		},
		_cropY(y) {
			if(y <= this.border) {
				return this.border
			}
			if(y + this.cropH >= this.windowHeight - this.containerTop - this.border) {
				return this.windowHeight - this.cropH - this.containerTop - this.border
			}
			return y
		}
	}
}
</script>
<style scoped lang="css">
@font-face {
	font-family: "iconfont";
	src: url('data:application/x-font-woff2;charset=utf-8;base64,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') format('woff2');
}
.vue-cropper {
	position: fixed;
	left: 0;
	right: 0;
	bottom: 0;
	z-index: 998;
	box-sizing: border-box;
	user-select: none;
	-webkit-user-select: none;
	-moz-user-select: none;
	-ms-user-select: none;
	direction: ltr;
	touch-action: none;
	text-align: left;
	background-image: url("");
}
.cropper-canvas {
	position: absolute;
	top: -9999px;
	left:-9999px;
	z-index: -998;
}
.vue-cropper .uni-info__ft {
	position: absolute;
	line-height: 48px;
	font-size: 18px;
	display: -webkit-box;
	display: -webkit-flex;
	display: flex;
	bottom: 0;
	left: 0;
	right: 0;
	z-index: 998;
}
.btn-group {
	position: absolute;
	right: 30px;
	bottom: 98px;
	z-index: 998;
}
.btn-item {
	position: relative;
	width:40px;
	height:40px;
	background:#fff;
	border-radius: 20px;
	display: inline-block;
	margin-left: 10px;
	text-align:center; line-height:40px;
}
.btn-item:active {background: #ccc;}
.rotate-btn {
	font-family: "iconfont" !important;
	font-size:30px;
	font-style: normal;
	-webkit-font-smoothing: antialiased;
	-moz-osx-font-smoothing: grayscale;
}
.rotate-btn:before {
	content: "\e65c";
	margin-left: -2px;
}

.reset-btn {
	font-family: "iconfont" !important;
	font-size:30px;
	font-style: normal;
	-webkit-font-smoothing: antialiased;
	-moz-osx-font-smoothing: grayscale;
}
.reset-btn:before {
	content: "\e648";
	margin-left: -2px;
}

.vue-cropper .uni-info__ft:after {
	content: " ";
	position: absolute;
	left: 0;
	top: 0;
	right: 0;
	height: 1px;
	border-top: 1px solid #d5d5d6;
	color: #d5d5d6;
	-webkit-transform-origin: 0 0;
	transform-origin: 0 0;
	-webkit-transform: scaleY(.5);
	transform: scaleY(.5);
	z-index: 998;
}

.vue-cropper .uni-modal__btn {
	display: block;
	-webkit-box-flex: 1;
	-webkit-flex: 1;
	flex: 1;
	color: #3cc51f;
	text-decoration: none;
	-webkit-tap-highlight-color: rgba(0,0,0,0);
	position: relative;
	text-align: center;
	background-color: #fff;
	z-index: 998;
}

.vue-cropper .uni-modal__btn:first-child:after { display:  none }
.vue-cropper .uni-modal__btn:after {
	content: " ";
	position: absolute;
	left: 0;
	top: 0;
	width: 1px;
	bottom: 0;
	border-left: 1px solid #d5d5d6;
	color: #d5d5d6;
	-webkit-transform-origin: 0 0;
	transform-origin: 0 0;
	-webkit-transform: scaleX(.5);
	transform: scaleX(.5);
	z-index: 998;
}

.vue-cropper .uni-modal__btn:active {
	background-color: #eee;
}

.cropper-box,
.cropper-box-canvas,
.cropper-drag-box,
.cropper-crop-box,
.cropper-face {
	position: absolute;
	top: 0;
	right: 0;
	bottom: 0;
	left: 0;
	user-select: none;
	z-index: 998;
}

.uni-image {
	width: 100%;
	height: 100%;
}

.cropper-box-canvas image {
	position: relative;
	text-align: left;
	user-select: none;
	transform: none;
	max-width: none;
	max-height: none;
	z-index: 998;
}

.cropper-box {
	overflow: hidden;
}

.cropper-move {
	cursor: move;
}

.cropper-crop {
	cursor: crosshair;
}

.cropper-modal {
	background: rgba(0, 0, 0, 0.5);
}

.pointer-events {
	pointer-events:none;
}

.cropper-crop-box {
	/*border: 2px solid #39f;*/
}

.cropper-view-box {
	display: block;
	overflow: hidden;
	width: 100%;
	height: 100%;
	outline: 1px solid #39f;
	outline-color: rgba(51, 153, 255, 0.75);
	user-select: none;
}

.cropper-view-box image {
	user-select: none;
	text-align: left;
	max-width: none;
	max-height: none;
}

.cropper-face {
	top: 0;
	left: 0;
	background-color: #fff;
	opacity: 0.1;
}

.crop-line {
	position: absolute;
	display: block;
	width: 100%;
	height: 100%;
	opacity: 0.1;
	z-index: 998;
}

.line-w {
	top: -3px;
	left: 0;
	height: 5px;
	cursor: n-resize;
}

.line-a {
	top: 0;
	left: -3px;
	width: 5px;
	cursor: w-resize;
}

.line-s {
	bottom: -3px;
	left: 0;
	height: 5px;
	cursor: s-resize;
}

.line-d {
	top: 0;
	right: -3px;
	width: 5px;
	cursor: e-resize;
}

.crop-point {
	position: absolute;
	width: 8px;
	height: 8px;
	opacity: 0.75;
	background-color: #39f;
	border-radius: 100%;
	z-index: 998;
}

.point-lt {
	top: -4px;
	left: -4px;
	cursor: nw-resize;
}

.point-mt {
	top: -5px;
	left: 50%;
	margin-left: -3px;
	cursor: n-resize;
}

.point-rt {
	top: -4px;
	right: -4px;
	cursor: ne-resize;
}

.point-ml {
	top: 50%;
	left: -4px;
	margin-top: -3px;
	cursor: w-resize;
}

.point-mr {
	top: 50%;
	right: -4px;
	margin-top: -3px;
	cursor: e-resize;
}

.point-lb {
	bottom: -5px;
	left: -4px;
	cursor: sw-resize;
}

.point-mb {
	bottom: -5px;
	left: 50%;
	margin-left: -3px;
	cursor: s-resize;
}

.point-rb {
	bottom: -5px;
	right: -4px;
	cursor: se-resize;
}
</style>